Strap sealing tool



Jan. 13, 1959 J. J. PACHTER STRAP SEALING TOOL 5 Sheets-Sheet 1 Filed. Feb. 16, 1955 INVENTOR.

JOHN J. PAOH TER ATTORNEYS Jan. 13, 1959 Filed Feb. 16, 1955 J. J. PACHTER 2,868,048

STRAP SEALING TOOL 3 Sheets-Sheet 2 a ENTOR.

JOHN J/ ACHTE/Q A TI'OIPONE Y 's Jan. 13,1959 J. J. PACHTER 2,868,048

STRAP SEALING TOOL Filed Feb. 16, 1955 5 Sheets-Sheet 3 INVENTOR. JOHN J PA CH 7'5? ATTORNEYS United States Patent 2,868,048 STRAP SEALING TOOL John J. Pachter, Harvey, 11]., assignor to Acme Steel Company, Chicago, 111., a corporation of Illinois Application February 16, 1955, Serial No. 488,543

6 Claims. (Cl. 81--9.1)

This invention relates to improvements in strap sealing tools adapted for use in forming interlocking joints between the overlapping ends of metal straps employed in reinforcing boxes or packages or in binding together a group of load units in the loading of freight cars and other carriers.

It has been the common practice to form joints between overlapping strap ends by crimping or sealing tools having parts which are actuated by relatively movable lever arms to deform the overlapping strap ends and also, usually, surrounding metal seals, thereby providing interlocking connections between the strap ends. It has been found that accidents have been caused by the failure of joints produced in-this manner, due to the fact that the sealing tools have not been operated to the full extent to complete the joints, so that the strap ends have pulled apart when subjected to severe strain.

The principal object of the present invention is to overcome the abovementioned difficulty by providing a strap sealing tool which is so constructed that a complete joint forming operation is insured each time thatthe actuationof the tool for that purposeis initiated. Another object of the invention is to provide a strap sealing tool having joint forming parts actuated by relatively movable lever arms, in combination with means for preventing the release of the tool from the joint until the relative movement of the lever arms has been'carried out to the extent required to produce a complete joint. A further object is to provide a strap sealingtool having joint forming parts operated by relatively movable lever arms, wherein a plurality of operations of the lever arms may be necessary to form a complete joint, in combination with means for insuring the completion of the required number of operations of said lever arms when the first operation thereofhas once been initiated. Still another object of the invention is to provide a strap sealing tool having relatively movable joint forming parts and means for operating them, in combination with means for causing them to assume automatically their normal positions after a joint has been completed. Other objects relate to various features of construction and arrangementwhich will appear more fully hereinafter.

The nature of the invention will be understood from the following specification taken with the accompanying drawings in which one embodiment is illustrated. In the drawings,

Figure 1 shows a side elevation of the improved sealing tool when it is in its open position to receive. the strap ends and the surrounding seal, parts of the operating levers being broken away;

Fig. 2 shows an end elevation of the tool illustrate in Fig. 1, looking toward the right as viewed in Fig. 1;

Fig. 3 shows .an enlarged side elevation similar to that of Fig. 1, with parts thereof broken away, illustrating the condition of the tool when it has been operated to effect the partial formation of a joint;

Fig. 4'shows a sectional view taken on the line 4-4 of Fig 3;

"ice

Fig. 5 shows a sectional view taken on the line 5-5 of Fig. 1 with parts of the apparatus removed;

Fig. 6 shows a partial view similar to that of Fig. 3 illustrating the relative positions of certain parts after the strap joint has been completed; and

Fig. 7 is a perspective view of one type of strap joint adapted to be formed by the sealing tool of the present invention.

In Fig. 7 of the drawings there is shown a strap joint comprising a metal strap of steel or the like having overlapping ends 10a and 10b which are enclosed by a surrounding tubular metal seal 11. The seal 11 is initially in the form of a fiat sleeve through which the strap ends 10a and 1012 are threaded, after which the strap is drawn taut around the box or package or group of load units to be reinforced, and the sealing tool is then operated to deform the lateral edges of the strap and seal to provide depressions 12 which cause portions of the seal and the enclosed strap ends to interlock with each other, thus providing an interlocking joint. Instead ofrnerely deforming the edge portions of the seal and the strap ends as shown at 12, these lateral edge portions may be transversely sheared at spaced points and the portions of the metal between the shear lines may be deflected to' provide another well known type of interlocking joint.

The sealing tool of the present invention is adapted to produce an interlocking joint such as that shown in Fig. 7 by means of cooperating relatively movable parts which are operated by relatively movable lever arms when the tool has been placed in a position to embrace the seal and overlapping strap ends. This tool is illustrated as comprising a frame or casing 14 having forwardly extending portions in the form of flanges 14a which are spaced apart and which have secured to their extremities, by means of screws 15, a front plate 16. The front plate 16 has laterally extending wings 16a which are also secured to the vertical portion 14b of the casing by means of bolts 17 and nuts 17a. The casing portion 14b has downwardly extending spaced ears 14c and the front plate 16 has similar downwardly extending ears formed on the wings 16a, thus providing registering rectangular recesses 18 which are adapt ed to receive the seal and the enclosed strap ends, when .the parts are in the relative positions shown in Figs. 1

and 2, preliminary to the formation of the interlocking joint.

The bolts 17 have pivotally mounted thereon two relatively movable jaws 19, each comprising a pair of bending dies 20 provided at their lower ends with inturned hooked extremities 20a which normally occupy the relative positions shown in Fig. 2 but which may be projected inwardly as shown in Fig. 4 during the process of forming the interlocking joint. The two bending dies 20 of each jaw 19 receive between them a circular deforming die 21 which is rotatably mounted upon the associated blot 17 and which is provided with an annularsemicircular surface 21a adapted to coact with an outer edge of the seal 11 to produce the type of deformation 12 which is shown in Fig. 7. As shown in Fig. 2, the dies 21 extend partially into the recesses 18 and, when the jaw portions 20a are closed upon each other on opposite sides of the seal, theseal and the enclosed strap ends are pushed upwardly into engagement with the dies 21 and against the lower edges 14d and 16d of the easing and the front plate, respectively. The form of the jaws 19 and the dies 21 does not constitute a part of the present invention but is claimed in the copending application of James M. Thornbery and James N.'Wognum, Serial No. 480,244, filed January 6, 1955.

The bending dies 20 are provided with upwardly extending arms 20b which are pivotally connected by pins 22 with links 23 and 24 which have their outer extremities extend- Patented Jan. 13, 1959 ing between the arms 20b of the jaws. These links 23 and 24 are pivotally connected to each other by a pin 25, as shown particularly in Figs. 3 and 4, one of the links 24 having spaced-ears 24a: atits end whichare located on opposite, sides of-the extremity of the link 23. The pin 25 also has: a pivotal engagement \with a rack bar 27 which is mounted to slide vertically in thecasing 14 and in the front plate 16 and to be actuated for the purpose ofelfecting relative movement of the jaws 19 in the formation of a joint. The rack bar 27 is provided along its rear edge with a rib 27a adapted to slide vertically in a groove 14e formed in the casing 14 and this rib hasformed thereon a series of rack teeth 27b through which'the vertical movement of the rack bar is effected. At its forward edge,-the rack bar 27 is provided with an, enlarged portion 270 which is adapted to slide in a guideway 16s formed in the front plate 16. The rib 27c is provided with a vertical groove 27d having .a rounded 'shoulder- 27e atits lower endand this groove isadapted to be engaged by a pin 28 mounted in the front plate 16 so that the extent of the upward movement. of the rack bar 27 is thereby limited.

The casing 14 has a rearwardly extending tubular portion14f in which an operating lever or handle 30 is secured by means of a pin 31. Another operating lever or'handle 32 is adapted to move vertically in the plane of the lever arm 30 and to effect the rotation of a pinion 33 which has a series of teeeth 33a adapted to mesh with the teeth 27b of the rack bar and also a pair of large teeth 33b and 330 which are separated by an intervening depression 33d. For this purpose, the lever arm 32 is secured at its inner end to a yoke 34 having side flanges 34a which are pivotally mounted upon the hollow shaft 33e of the pinion 33, as shown in Figs. 3 and 5. This hollow'shaft is journaled in bearings in the flanges 14g of the casing 14 and has mounted therein a coil spring 35 adapted to be wound up during the operation of moving the rack bar 27 upwardly to form a joint, after which the spring is adapted to unwind to rotate the pinion 33 and thereby restore the rack bar 27 and the jaws 19 to their original positions. This spring has an extremity 35a secured in the end wall of the hollow shaft 33, as shown in Fig. 5, and the other end of the spring has an extremity 35b secured in an aperture formed in a plate 36, which is secured to a flange 14g by screws'36a,-so that when the pinion 33*is rotated 'withrespect to the flanges 14g there is a winding or unwinding of the spring.

The rotation of the pinion 33 by reciprocation of the lever arm- 32 is effected by a pawl 37 which is rotat ably mounted in apertures formed in the side flanges 34a of the yoke 34. This pawl has mounted thereon a coil spring 38 having an arm 38:: engaging a part of the yoke 34 so that the pawl 37 is normally rotated by thespring to cause a tooth 37a at one end of the flat face 37b of the pawl to engage a tooth of the pinion 33. Thus, when the lever arm 32 is moved upwardly fromthe position-shown in Fig. 3, theflat face 375 of the pawl slides over the large tooth 33c, without rotation of the pinion 33. However, when the lever 32 is moved downwardly from the'position shown in Fig. 1, the pinion 33 is rotatedina clockwise direction as the tooth 37a' of the pawl 37 engages a recess or depression between two teeth of the pinion, such as the, depression 33d, and the rack bar is thereby elevated to cause the jaws 19 to close upon the seal and the strap ends.

The-sealingtool shown in the drawings is one in which a plurality of reciprocations of the operating lever arm 32 'are required inorder to effect the formation of a complete joint by the action of the bending dies 20 and the deforming dies 21.1 In order to hold the rack bar 27 in the-position to which it has been moved by gone operation of'the lever arm 32, pending further actuation thereof by -a subsequent movement of the .lever arm, a detent -40-is provided for engagement withthe teeth 27b-of the'rack bar. The detent 40 is journaledin bear-= ings in the flanges 14g of the casing 14 and it has mounted thereon a coil spring 41 which has one end fixed ina slot in the detent and the other end thereof arranged to engage the adjacent flange 14g so that the spring tends normally to turn the detent 40 to a position where the tooth 40a thereof will engage the teeth 27b of the rack bar. The tooth 40a is located at one end of a flat surface 4% and when the detent is turned to the position shown in Fig. 6,-the tooth 40a is moved out of engagement with the teeth ofthe rack bar and the rackbar is then free to move past the flat surface 40b. When the rack bar has been moved upwardly by the rotation of the pinion 33 it 'is normally held in the position to which it has been moved by the tooth 40a which is actuated by the spring 41 and this condition is maintained until the rack bar is released by the rotation of the detent. This release is effected by a releasing plate 2 which is journaled on the hollow shaft 339- of the pinion 33 and which is provided with anaperture engaged by the extremity of the detent'40. This aperture has a wall providing a flat surface 42a which is adapted to contact with a flat surface 400 on the detent 40 for the purpose of rotating the detent in a clockwise direction, as viewed in Fig. 3, and thereby releasing the rack bar 27. At the other end of the aperture in the plate 42 there is a curved surface 40d which is adapted to conform to the curved surface of the detent 40 opposite to the flat, surface 400. The plate 42 is adapted to be moved to a position where it will actuate the detent 40 to release the rack bar 27 upon movement of the lever arm 32 upwardly to a sufficient extent to cause-the flat surface 37b of the pawl 37 to engage a radially extending shoulder 420 formed on the plate 42 on the side thereof opposite to the surface 4211. Upon engagement of the pawl 37. with theflat surface 420, the releasing plate 42 is rotated ina counterclockwise direction until the surface 42a of the plate engagesthe surface 400 of the detent, whereupon the rack bar. is released.

The plate 42 serves also to prevent .the release of the rack bar 27 until the jaws '19 have been fully operated to form a complete joint. This control iseflected by a transversely extending flange 42d which is formed upon an arm-42a of the plate and which is adapted to occupy a position between the rib 27a of the rack bar and a parallel vertically extending rib27f which is formed thereon.' When a joint has been partially formed and the flange. 42d of the releasing plate occupies a position within the channel 43-between the ribs 27a and27f, the releasing plate 42- is prevented from being rotated by the engagement of the pawl 37 with the surface 420 of the plate so that it is impossible to release the rack bar from the detent 40 when a joint is only partially formed.

At the commencement of a sealing operation with the rack bar- 27 in its extreme upper position, as shown in Figfil, the arm 42a and the flange 42d of the releasing plate occupy positions above therib 27f but, as the lever 32 .isrotated in a clockwise direction, the releasing plate 42 is turned by frictional contact with the pinion or by the engagement of the flange 42d with the upper end of the rib 27 with the result that, when the initial stroke of the lever 32 'hasbeen completed, the flange 42d will occupy a position between the ribs 27aand 27 as shown in Fig. 3. The lever 32 may then be raised again to an upper position in readiness for a second stroke and, during this operation,. the spring actuated pawl 37 will ride over the teeth of the pinion 33 and the rack bar 27 will be held stationary by theengagement 'of the detent 40 with one of the teeth 27b. Upon the completion of this second. stroke of the operating lever 32', the joint is completed and the flange 42d will have passed to a position below the rib 27) so that it is no longer confined to the channel 43.' Upon again moving the lever. 32 in a counterclockwise direction, .withtheflange42d released from the channel 43, the releasing. plate 42-is then rotated by tbs, gngagment of the pawl 37 with the surface 420 to the position shown in Fig. 6, thereby causing the surface 42a of the releasing plate to engage the surface c of the detent 40 and release the tooth 40a from engagement with the teeth 27b of the rack bar.

This release operation is followed by the rotation of the pinion 33 under the influence of the coil spring 35 which will have been wound up by the rotation of the pinion 33 during the joint forming operation. This causes the pinion to be actuated by the spring to return the rack bar and the jaws to the normal open position shown in Figs. 1 and 2.

In order to control the two stage operation of the tool in forming a joint by two successive operations of the lever 32, the pinion 33 is provided with the large teeth 33b and 330 separated by the intervening recess 33d as previouslydeseribed. In the initial position of the lever 32 as shown in Fig. 1, the pawl 37 rests upon the tooth 33c but, upon movement of the lever 32 in a clockwise direction, the pawl 37 engages the first small tooth 33a, whereupon the pinion is rotated to the position shown in Fig. 3, thereby partially elevating the rack bar 27. The lever 32 must then be rotated again in a clockwise direction for the second stroke and the pawl 37 then engages the recess 33d at the end of the large tooth 33c and, during the second downward stroke of the lever 32, the pinion 33 is rotated by the engagement of the pawl 37 with the recess 33d. Upon the completion of this second stroke the rack bar 27 has reached the upper limit of its travel as determined by the engagement of the pin 28 with the shoulder 27e at the bottom of the groove 27d in the rack bar. Thus, the limit of the upward movement of the rack bar is determined by the pin 28 and, even though a further stroke of the lever 32 might be attempted, it could not accomplish further movement of the rack bar because of the pine 28 and because the pawl 37 would then ride upon the extended outer surface of the tooth 33b.

From the foregoing description it will be apparent that means have been provided for insuring a complete formation of a joint when the operation of the tool has once been initiated with a seal and the enclosed overlapping strap ends positioned between the jaws which are initially separated from each other as shown in Fig. 2. This result is attained even though more than one stroke of the operating lever 32 is required in order to effect the formation of a complete joint, since means are provided for automatically holding the rack bar 27 and the jaws 19 at the intermediate stage shown in Figs. 3 and 4. In the operation of the tool the lever arm 30 is conveniently held in one hand of the operator and the other lever arm 32 is manipulated with the other hand. The lever arms 30 and 32 are located in a vertical plane which extends at right angles to the plane of the relative movement of the jaws 19 and the tool may thus be operated conveniently to cause the open jaws 19 to embrace a seal and a strap where the strap is located in alignment with the lever arm 30 by which the tool is supported.

Although one form of the invention has been shown and described by way of illustration, it will be understood that it may be constructed in various other embodiments which come within the scope of the appended claims.

I claim:

1. The combination in a tool adapted to form a joint between a metal seal and enclosed overlapping strap ends, of relatively movable parts adapted to deform said seal and the overlapping strap ends to form an interlocking joint, means for actuating said parts including a reciprocating member adapted to move through a forward stroke to actuate said parts to form a joint and to move through a reverse stroke to retract said parts from the joint, a rack bar carried by said member, a pinion for actuating said rack bar, a pivoted lever arm, a pawl carried by said lever arm and adapted to engage said pinion, and a detent for engaging said rack bar to hold said reciprocating member after a partial forward stroke thereof.

2. i The combination in a tool adapted to form a joint between a metal seal and enclosed overlapping strap ends, of relatively movable parts adapted to deform said seal and the overlapping strap ends to form an interlocking joint, means for actuating said parts including a reciprocating member adapted to move through a forward stroke to actuate said parts to form a joint and to move through a reverse stroke to retract said parts from the joint, a rack bar carried by said member, a pinion for actuating said rack bar, a pivoted leverarm, a pawl carried by said lever arm and adapted to engage said pinion, a detent for engaging said rack bar to hold said reciprocating member after a partial forward stroke thereof, and means mounted in proximity to said pinion and actuated by said lever arm for disengaging said pawl from said pinion and said detent from said rack bar.

3. The combination in a tool adapted to form a joint between a metal seal and enclosed overlapping strap ends, of relatively movable parts adapted to deform said seal and the overlapping strap ends to form an interlocking joint, means for actuating said parts including a reciprocating member adapted to move through a forward stroke to actuate said parts to form a joint and to move through a reverse stroke to retract said parts from the joint, a rack bar carried by said member, a pinion for actuating said rack bar, a pivoted lever arm, a pawl carried by said,

lever arm and adapted to engage said pinion, a detent for engaging said rack bar to hold said reciprocating member after a partial forward stroke thereof, and means mounted in proximity to said pinion and actuated by said lever arm for disengaging said pawl from said pinion and said detent from said rack bar, and means adapted to enact with parts carried by said reciprocating member for preventing the operation of said last named means until said reciprocating member has completed a full forward stroke.

4. The combination in a tool adapted to form a joint between a metal seal and enclosed overlapping strap ends, of relatively movable parts adapted to deform said seal and the overlapping strap ends to form an interlocking joint, means for actuating said parts including a reciprocating member adapted to move through a forward stroke to actuate said parts to form a joint and to move through a reverse stroke to retract said parts from the joint, a rack bar carried by said member, a pinion for actuating said rack bar, a pivoted lever arm, a pawl carried by said lever arm and adapted to engage said pinion, a detent for engaging said rack bar to hold said reciprocating member after a partial forward stroke thereof, means mounted in proximity to said pinion and actuated by said lever arm for disengaging said pawl from said pinion and said detent from said rack bar, and means including a spring for then rotating said pinion to move said rack bar through a reverse stroke and thereby returning said parts to their original positions.

5. The combination in a tool adapted to form a joint between a metal seal and enclosed overlapping strap ends, of relatively movable parts adapted to deform said seal and the overlapping strap ends to form an interlocking joint, means for actuating said parts including a reciprocating member adapted to move through a forward stroke to actuate said parts to form a joint and to move through a reverse stroke to retract said parts from the joint, a rack bar carried by said member, a pinion for actuating said rack bar, a pivoted lever arm, a pawl carried by said lever arm and adapted to engage said pinion, a detent for engaging said rack bar to hold said reciprocating member after a partial forward stroke thereof, and a releasing plate movable about the axis of said pinion to release said pawl from said pinion and said detent from said rack bar, said releasing plate having a part engageable by said lever upon the reverse stroke of said lever for turning said plate to effect said release.

6. The combination in a tool adapted to form a joint between a metal seal and enclosed overlapping strap ends,

of relatively movable parts adapted to deform said seal and the overlapping strap ends to form an interlocking joint, means for actuating said parts including a reciproeating member adapted to move through a forward stroke to actuate said parts to form a joint and to move through a reverse stroke to retract said parts from the joint, a rack bar carried by said member, a pinion for actuating said rack bar, a pivoted lever arm, a pawl carried by said lever arm and adapted to engage said pinion, a detent for engaging said rack bar to hold said reciprocating member after a partial forward stroke thereof, a releasing plate movable about the axis of said pinion to release said pawl from said pinion and said detent from said rack bar, said releasing plate having a part engageable by said lever upon the reverse stroke of said lever for turning said plate to effect said release, said reciprocating member having parallel ribs thereon, said releasing plate having a flange adapted to enter between said ribs after a single operation of said lever and a partial forward stroke of said reciprocating member to prevent the release of said pawl and said detent until after a lull forward stroke of said reciprocating member.

References Cited in the file of this patent UNITED STATES PATENTS 487,346 Cheeseman Dec. 6, 1892 591,779 Hagstrom Oct. 12, 1897 1,897,511 Taylor Feb. 14, 1933 1,984,652 Ott Dec. 18, 1934 1,996,202 Harvey Apr. 2, 1935 2,181,755 Adamson Nov. 28, 1939 2,725,771 Arnold Dec. 6, 1955 

